Topic Four (1.4): Arithmetic sequences

Introduction

A sequence is a set of numbers that follow a pattern. In this topic, you are going to look at two ways that we describe sequences by referring to the numbers in the sequence as terms. The first is a term-to-term rule that tells you how to get from one term to the next. We then look at describing a sequence using the position-to-term rule, which works out the value of the term from its position in the sequence. This is also known as the 'nth' term.

Warm Up

First complete the skill checker on page 1.

Note: If you need a refresher on substitution, try watching this video:

Working through your course book

This video shows how to generate a sequence when you are given a term-to-term rule:

This video shows how to describe the term-to-term rule when you are told the sequence. Note how we need to give two pieces of information – both the common difference (in other words, what number you add or subtract when moving from one term to the next) and also what the first term of the sequence is:

Next watch this video, which demonstrates how you would use a position-to-term rule:

Read and make notes on pages 1-3, copying out the worked examples, if you think it will help you.
Now see if you can answer the Band 2 questions on pages 5-7.
For more questions please COMPLETE - 1.1 worksheet Arithmetic sequences
If you would like more practice, then work through these lessons on the MyMaths website:

EXPLORE – Sequences (MyMaths) Links to an external site. [Not available on sample course]

EXPLORE – Arithmetic sequences (MyMaths) Links to an external site. [Not available on sample course]